I never took molybdenum for die off (did not know it existed when I was going through my worst die off stage), but I survived (somehow), so it is possible. Going to the public bath (which has a sauna) helped, as did eating more in terms of grains (buckwheat/millet in my case). But for the most part, I just took a lot of sick days >_>
Anyway, on the topic of the kimchi, there are three things to be wary of. One is the sugar, as you noted. I’d also be a little concerned about the salt (probably table salt), and possibly the paprika (some people don’t do well with nightshades, of which paprika is one). Chili peppers/spicy foods can also be a problem for some people. Otherwise, it looks like you’ve found yourself a good product. Except! I recently bought some homemade, additive-free kimchi here in Japan that didn’t have added sugar, but did have table salt, carrots, and apple. I think I had a mild reaction (headache) to something, so I’m going to wait before eating it again. The best thing to do is to make it yourself, but that seems like too much work… Also, you have to keep the stuff sitting around somewhere for three weeks.
If you’re still going through die off, I’d say it’s likely to be a little too early for commercial kimchi, or depending on your reaction to chilis, too early for any kind of kimchi.